Radio-frequency identification (RFID) is a technology that uses communication via radio waves to exchange data between a reader and an electronic tag attached to an object, for the purpose of identification and tracking. Generally, an radio-frequency identification system involves RFID readers, RFID tags, and an application system. It is noted that the RFID system can be designed to operate using RFID tags of different radio frequencies under different regulations, including low-frequency (LF) RFID tags at 134 KHz typically, high-frequency (HF) RFID tags at 13.56 MHz, ultra-high-frequency (UHF) RFID tags at 860˜960 MHz, and microwave RFID tags at 2.4 GHz, and so on. The passive RFID tags have no power source internally and require an external electromagnetic field, that is mostly emitted from RFID readers, to power and activate an internal analog circuit embedded in the passive RFID tags for the chip operations. Generally, such RFID tag can be embedded with memories for data storage, and the memories can be read-only memories (ROM), write-once-read-many (WORM) memories or electrically erasable programmable read-only memories (EEPROM). Since the passive RFID tags and readers utilize the electromagnetic waves to transfer energy and signals, and their signal transmission performance, especially the frequency response of the RFID tags' antennas, can easily be affected by the material characteristics of the objects on which the RFID tags are attached, or even by the metallic objects as well as the conductive materials that are located neighboring thereto. That is, the metallic objects as well as the conductive materials, whichever are distributed neighboring to an RFID tags, will cause an interference phenomenon to be generated by a degree depending on the volume/area of those objects and also the distances there between, that will affect the reading performance of the RFID system. Moreover, since the electromagnetic waves used for signal transmission in the RFID system are invisible waves, neither the constructive interference nor the destructive interference caused by those surrounding metallic objects or conductive materials are not perceptible.
It is noted that most conventional storage cabinets are generally formed as an open-frame shelf rack composed of a plurality of posts and a plurality of partitions, whereas most of the partitions are made of plastic or wood. Under a condition when it is required to manage the storage capacity of a cabinet to a precision that allows the stocks in each and every compartment of the cabinet to be inventoried, such inventory operation for the conventional storage cabinet is generally very difficult to be automated, but instead will consume a mass amount of manpower, time and resources. Thus, it is usually for a store to close for the day just for performing the inventory operation, which is not only bad for business, but also is inconvenient to his/her consumers for shopping. On the other hand, if the inventory is not performed accurately, the operation of the store can be troubled by many problems, including: hot selling items are in short supply, but the slow selling items are in plenty, and some items in the store had exceeded their expiration dates. Overall, poor inventory can cause resource scheduling problem to the store, resulting in not only the increasing in the waste of substance as some items in the store may exceed their expiration dates before being sold, but also the increasing in the waste of storage capacity as those items that are slow selling or had expired can be left unnoticed on the shelves. The aforesaid problem can also be found in the field of library management since in most library, the on-shelf, off-shelf, book-searching and book inventory are performed manually by librarians that can be a very time-consuming and labor-intense operation.